Darwin: Fix incorrect mutex protection of libusb_darwin_acfl global

[platform/upstream/libusb.git] / libusb / os / darwin_usb.c

diff --git a/libusb/os/darwin_usb.c b/libusb/os/darwin_usb.c
index 0af4e3c..f092562 100644 (file)
--- a/libusb/os/darwin_usb.c
+++ b/libusb/os/darwin_usb.c
@@ -30,6 +30,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <libkern/OSAtomic.h>
 
 #include <mach/clock.h>
 #include <mach/clock_types.h>
@@ -55,7 +56,7 @@ static clock_serv_t clock_realtime;
 static clock_serv_t clock_monotonic;
 
 static CFRunLoopRef libusb_darwin_acfl = NULL; /* async cf loop */
-static int initCount = 0;
+static volatile int32_t initCount = 0;
 
 /* async event thread */
 static pthread_t libusb_darwin_at;
@@ -311,6 +312,12 @@ static void *event_thread_main (void *arg0) {
   struct libusb_context *ctx = (struct libusb_context *)arg0;
   CFRunLoopRef runloop;
 
+  /* Set this thread's name, so it can be seen in the debugger
+     and crash reports. */
+#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060
+  pthread_setname_np ("org.libusb.device-detach");
+#endif
+
   /* Tell the Objective-C garbage collector about this thread.
      This is required because, unlike NSThreads, pthreads are
      not automatically registered. Although we don't use
@@ -332,7 +339,7 @@ static void *event_thread_main (void *arg0) {
   /* add the notification port to the run loop */
   libusb_notification_port     = IONotificationPortCreate (kIOMasterPortDefault);
   libusb_notification_cfsource = IONotificationPortGetRunLoopSource (libusb_notification_port);
-  CFRunLoopAddSource(CFRunLoopGetCurrent (), libusb_notification_cfsource, kCFRunLoopDefaultMode);
+  CFRunLoopAddSource(runloop, libusb_notification_cfsource, kCFRunLoopDefaultMode);
 
   /* create notifications for removed devices */
   kresult = IOServiceAddMatchingNotification (libusb_notification_port, kIOTerminatedNotification,
@@ -351,11 +358,9 @@ static void *event_thread_main (void *arg0) {
 
   usbi_info (ctx, "thread ready to receive events");
 
-  /* let the main thread know about the async runloop */
-  libusb_darwin_acfl = CFRunLoopGetCurrent ();
-
   /* signal the main thread */
   pthread_mutex_lock (&libusb_darwin_at_mutex);
+  libusb_darwin_acfl = runloop;
   pthread_cond_signal (&libusb_darwin_at_cond);
   pthread_mutex_unlock (&libusb_darwin_at_mutex);
 
@@ -378,7 +383,7 @@ static void *event_thread_main (void *arg0) {
 static int darwin_init(struct libusb_context *ctx) {
   host_name_port_t host_self;
 
-  if (!(initCount++)) {
+  if (OSAtomicIncrement32Barrier(&initCount) == 1) {
     /* create the clocks that will be used */
 
     host_self = mach_host_self();
@@ -401,7 +406,7 @@ static int darwin_init(struct libusb_context *ctx) {
 }
 
 static void darwin_exit (void) {
-  if (!(--initCount)) {
+  if (OSAtomicDecrement32Barrier(&initCount) == 0) {
     mach_port_deallocate(mach_task_self(), clock_realtime);
     mach_port_deallocate(mach_task_self(), clock_monotonic);